Method for preventing the growth of fungi in leathers, paints, foods and fabrics



United METHOD FOR PREVENTING TI GROWTH OF FUNGI IN LEATHERS, PAIN FOODS AND FABRICS James M. Constantin, Clark, T. William Humphreys, Plainfield, Henry B. Lange, Scotch Plains, Daniel Shew, Metuchen, and Joseph R. Wagner, Summit, N.J., assignors to Merck & Co., Inc., Rahway, N.J., a corporation of New Jersey No Drawing. Filed Jan. 22, 1959, Ser. No. 788,282

4 Claims. (Cl. 167-33) This invention relates to antimicrobial compositions, and has for its object the provision of compositions consisting of various fura n 'ompounds disper sgi in a carrier medium such as water, organic solvents or air" inert powder. The furan compounds used in compositions can be derived conveniently from hydroxymethylfurfural, and are characterized by having water-oil solubility making them effective in compositions for biological purposes.

The invention is based on our discovery that the furan compounds hereinafter described are effective against such organisms as: Aspergillus niger, Pseudomonas sp., Erwinia sp., Bacillus coagulans, Penicillium sp., and Saccharomyces cerevisiae. Many of the compounds are relatively non-toxic and can be used to advantage in various conditions and materials including food. Certain of these compounds have a vapor phase at ordinary temperature and can be used effectively in that form for protecting packaged goods.

Although the invention will be described with special reference to the antifungal and antibacterial action of the composition they are useful against a wide variety of virus including bacteriophages, against rickettsiae and against protozoa.

The low toxicity of the compounds is shown by standard tests. For example for -propionyloxymethylfurfural, the acute intraperitoneal LD for mice was 1950 mg./kg., and the acute oral LD for mice was 3500 mg./kg. The skin patch test (24-hour application on intact and abraded skin of an albino rabbit) failed to elicit signs of dermal irration.

The following are furan compounds used in compositions of the invention:

W R-OO O CHz-LQiCHO where R is CH CH3 2 CH CH CH C H CHCH CH =CH (CH COOH(CI-I COOH (CH MOOC(CH and where Z is a lower alkyl having up to 8 carbon atoms.

where R is CH C H CH =CHCH and;

.mijtmnt @EM U QLFUMUH it 3,080,279 Patented Mar. 5, 1963 I It I HO OH OHr-O-CHrL ono-k iornofi-n-fi-oonh lono Where R is (CH CH CH CH=CH, (CH and where R is CH;,-, CH CH C H and R is COOH(CH CO, and MOOC(CH ),;CO;

and R may be the same as or dissimilar from R HOCHz- GHzOH and ROOH2- -CH2OR where R is COOH(CH CO- and MOOC(CH CO--, wherein x in all the above compounds is 2, 3, 4, 5, 6, etc., and M is one of the metals of the group consisting of zinc, copper, cobalt, or sodium, calcium.

where R=CH C H and lower alkyls, C H and other aryls, C H N and heterocycles and etc.

R'=CH C H etc., lower alkyls and aryls and heterocyclic organic residue, and

R may or may not be the same as R.

Xmol J-CHZX 0 Where X=Cl, Br, halogens;

Kate 0 -CH0 where X=Cl, Br, F, etc.;

RO\ /OR /CH 425 R0 OR See ers organic phases and impart the antimicrobial activity. In addition, formulations of bentonite or continental clay with these compounds have utility for dispersing in the dry form where a slow release of activity may be desired.

The broad spectrum of compositions, activity and physical properties make these materials useful for combating microbial attack in foods, paints, plastics, fabrics, adhesives and in soaps, deodorants and air conditioning systems.

Compounds used in the compositions of the invention were screened by in vitro tests at 0.01 molar levels in potato dextrose agar (Difco) (pH 5.6 and 4.6) against Aspergillus niger, and in nutrient agar Difco (pH 6.8) against Erwinia sp. and Pseudomonas sp. Complete inhibition of fungi and bacteria for periods up to 120 hours was achieved with compositions of the invention. Cornpositions containing the compounds varying from 0.005 to 1 molar are effective and are useful over a wide pH range.

Various applications of compositions of the invention are illustrated in the following examples:

EXAMPLE I Reduction of Microbial Spoilage of Various Foods Pancake syrup-Commercial bottled pancake syrup was added to test tubes, 9 mL/tubes, to each of which was added separately one ml. of 0.1% by Weight aqueous 5-methoXy-methylfurfural, 5-propionyloxymethylfurfural, and hydroxy-methylfurfural-S-methylhexanoate. Two weeks storage at room temperature in unstoppered tubes showed no growth in any tube.

EXAMPLE II Counts/ gram Control 4.5 x S-acetoxymethylfurfural 0.8 x 10 5-butoxymethylfurfurai 1.0 X 10 Aureomycin 8.7 x 10 Sorbic acid 18.8 X 10 EXAMPLE III Ground beef-Ten grams of freshly purchased ground beef were placed in 50 ml. beakers. covered with Saran, and stored at 40 F. Final concentration of additives in the meat were water, 10%; 5-propionyloxymethylfurfural, 0.1%. After three days the bacterial count showed:

Counts/ gram Control 2.3 10 5-propionyloxymethylfurfural 1.4 x 10 EXAMPLE IV Clarified Orange juice.-Fresh orange was centrifuged to remove suspended solids. Nine mls. were placed in a. tube and 1 ml. of 0.1% methoxymethylfurfural was added to it. A second tube was left as is. Incubation was carried out at room temperature. After 3 days the optical density was determined as a measure of organism growth.

Sample: Optical density Control 0.845 Methoxymethylfurfural 0.05

Compositions for use in paints may comprise one or more of the compounds in a suitable solvent such as toluol, xylol, butanol, and mineral spirits. Such compositions are 1. suitable for use in oil base paints. For water-based paints, such as the so-called latex paints, it is preferred to add the composition to such paints as a 1:1 ratio of compound to Water with a suitable emulsifying agent such as Tweens or Spans to form an emulsion with the paint.

The amounts of compounds added to the paints may vary from 0.1 to 2% by weight for general purposes although these amounts may be varied for particular enduses.

The following formulations illustrate the compatibility of the compositions of the invention in various types of paints as antifungals:

EXAMFLE V Naval Ship PaintVinyl Ti0 15 gms. ZnO 55 gms. Lamp black 0.6 gm. Extender 40 gms. Plaskon gms. Mineral spirits 25 gms. Mill on a 3-roll mill 1 pass. Add vinyl solution VAGH 37.5 gms. MIBK 200 gms. Xylene 17 gms. Driers 0.3 gm.

To 10 gms. of this formula, 10 drops (or 0.5 gm.) of a :ter-S-propionyloxymethylfurfural emulsion containing 1% Tween 80.

Antifoam 1 gm. Mill on 3-roll mill 1 pass. Continue to add:

Methocel 2.5 gms. H O 40 gms. I-Iexylene glycol 7 gms. Diethylene glycol 15 gms.

Latex Dow F122A15 gms.

White pine panels were painted with a Saran latex paint andkin l al kydpaint (formulas of Examples V and VI) were exposed to As'p'ergillus niger in a test chamber. This test chamber contained a dish of water at 25 C. and the organism in potato dextrose agar. Control samples prepared without antifungal agent were also subject to the same conditions. After 4 to 6 weeks the treated panels were clear and bright while those not treated contained dark black spots scattered over the surface where attack took place. Signs of breakdown and peeling of the film were also noted.

EXAMPLE VII Bread:

2 cups milk cup sugar 4 teaspoons salt 2 ablespoons shortening (hydrogenated vegetable 2% cups water 1 packet active dry yeast 12 cups sifted flour (2612 gms.)

A 13.6% solution of 5-propionyloxymethyl furfurylidine dipropionate (I) in melted shortening was incorporated into one lot of dough in suificient quantity to provide a level of (I) equivalent to 4 ounces per 100 pounds of flour. In a like manner (I) was added to successive lots of dough to provide concentrations of 3 ounces, 2 ounces, and one ounce per 100 pounds of flour. In each case the formula was adjusted to compensate for the shortening contributed by the solution of (I). Another lot was treated by the addition of sodium propionate equivalent (II) to 4 ounces per 100 pounds of flour. A control lot was also prepared without the addition of either (I) or (II).

Each lot was allowed to rise 1.5 hours, punched down,

allowed to rest 10 minutes, divided into loaves, allowed to rise sufiiciently to double the volume and baked 10 minutes at 425 F. plus 25 minutes at 350 F.

The baked loaves were allowed to cool. Then the end was cut olf each loaf. Two loaves from each lot were sprayed with a suspension of Penicillium sp. spores, wrapped in punctured Cry-O-Vac film and placed in a B.O.D. box adjusted to 30 C. and containing a pan of water to maintain high humidity.

The loaves were examined periodically for the appearance of visible colonies of the mold. The results are summarized in the following table:

RATE OF MOLD DEVELOPMENT Days after Inoculation Treatment, oz./100 1b. flour 4 oz. I 3 oz. I 2 oz. I 1 oz. 1 4 oz. TI None 1 One small colony. 9 Single area x 2 inches. 1 Numerous colonies.

The following example illustrates the use of the compositions in the treatment of leather:

EXAMPLE VIII For the treatment of leather, an effective composition comprises a solution of 50 parts of the compound in 50 parts of a chlorinated solvent such as perchlorethylene. This is further diluted with a mixture of neats-foot and mineral oil and solvent so that a final concentration of active microbial agent is between 0.1-3%.

Percent Methoxymethylfurfural composition in perchlorethylene 1.0 Chlorinated solvent 75.0 Mineral oil 12.0 Neats-foot oil 12.0

EXAMPLE IX For the treatment of textile fabrics a suitable composition may consist of the compound in isopropyl or methyl alcohol of a 1:1 ratio diluted with 1-2 parts of water and containing 1-5% weight of an effective wetting agent such as given by the alkyl sulfonates, Tweens or Spans.

For example, a composition consisting of -proprionyloxymethylfurfural and water in a 1:1 ratio emulsified with 1% or less of Tween 80 or other suitable emulsifying agent imparts microbial protection to textile fabrics even when diluted down to 0.1% with additional water in a dip solution.

The compositions of the invention may also be used very effectively in pharmaceutical formulations. For example, suitable compositions for this purpose may comprise equal parts of the compound and a polyethylene glycol (Carbowax 300).

This active composition when added to a combination of ingredients, such as stearic acid, anhydrous lanolin, glycol stearate, sorbitol solution, isopropyl palmitate, and water, so that its final concentration is between 1 3% of the total, imparts the antibacterial-antifungal property desired.

As a feature of this invention we found that the triacyloxy derivatives of HMF, structure,

J l /0COR ROOOCH on 0 EXAMPLE X Finely powdered stannous chloride dihydrate was added to an ice cold solution of 126 grams of HMF in 300 grams of propionic anhydride. The mixture was stirred for two hours and then cooled in a refrigerator for sixteen hours. The black reaction mixture was poured into water and extracted with chloroform. The chloroform extracts were evaporated to yield a viscous black liquid which was extracted with 400 ml. of a 30% by volume ether-petroleum ether solution. The extracts were washed with aqueous solutions of sodium bicarbonate and sodium bisulfite. The organic phase was dried over magnesium sulfate and the solvent was removed under reduced pressure. The residue was vacuum distilled to yield pale yellow HMF tripropionate, B.P. .05 139-141", N 1.4680.

wherein R is a lower alkyl group.

2. A method for preventing the growth of fungi in edible foods comprising treating said edible food with a 8 composition containing from about 0.1% up to 1% by paint prior to application to said surfaces with a composiweight of a compound having the formula tion comprising 5-propiony1oxymethyl furfural and applying the resulting mixture to said surfaces. l 1 2 5 References Cited in the file of this patent K 0 UNITED STATES PATENTS H 1,548,077 Wallis Aug. 4, 1925 intimately mixed with an edible carrier, wherein R is 5 5 M11161 P' 9 selected from the group consisting of acyl and lower alkyl. 2,319,431 St llm et a1 y 1943 3. A method for preventing the growth of fungi in edible foods comprising treating said edible food with a OTHER REFERENCES composition comprising 0.5% S-acetoxymethyl furfural D l Th F l A,c s monograph #119 1953, in aqueous solution. pages 135, 182, 411-2, 267 and 268.

A method fOI the Preventiion 0f the growth 0f Blanksma: Chemical Abstracts, vol. 4, 1910, page 752;

fungi i paint pp to surfaces comprising mixing said Abstract of Chem. Weekblad, vol. 6, p. 717 (1909 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, a oao aw March 5 I963 Jamce Mo Constantin-e1; alo

hat error appears in the above numbered pat- It is hereby certified t that the said Letters Patent should read as ent requiring correction and corrected below.

Column 5,, EXAMPLE VII. footnote to the table for Single area 1/2 X 2 imzhes read 2 Single area 1 1/2 2 inchesa o Siitgned and seaIed thia 24th day of September 1963;,

( SEAL) Attest:

DAVID L. LADD Commissioner of Patents ERNEST W SWIDEE Attesting Officer 

1. METHOD FOR PREVENTING THE GROWTH OF FUNGI IN LEATHERS, PAINTS, FOODS AND FABRICS WHICH COMPRISES APPLYING TO SAID MATERIALS A COMPOSITION COMPRISING A COMPOUND HAVING A FORMULA SELECTED FROM THE GROUP CONSISTING OF 